A high hemoglobin count indicates an above-average concentration of the oxygen-carrying protein hemoglobin in your blood. Hemoglobin (Hg or Hgb) is the main component of red blood cells. Hemoglobin count - also referred to as hemoglobin level - indicates your blood's oxygen-carrying capacity.

A high hemoglobin count is somewhat different from a high red blood cell count, because each cell may not have the same amount of hemoglobin proteins. Therefore, you could have a high hemoglobin count even if your red blood cell count falls within the normal range.

The threshold for a high hemoglobin count is slightly different from one medical practice to another. It's generally defined as more than 17.5 grams (g) of hemoglobin per deciliter (dL) of blood for men and 15.5 g/dL for women. In children, the definition of a high hemoglobin count varies with age and sex.

A high hemoglobin count is rarely an unexpected finding or simply discovered by chance. It's usually found when your doctor has ordered tests to help diagnose a condition you're already experiencing. Talk to your doctor about what these results mean. A high hemoglobin count and results from other tests may already indicate the cause of your illness, or your doctor may suggest other tests to check your condition.

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